FedML-AI FedML MQTT+S3 Communication Backend remote_storage.py S3Storage.read_model deserialization

A weakness has been identified in FedML-AI FedML up to 0.9.6. Affected by this issue is the function S3Storage.read_model of the file fedml/core/distributed/communication/s3/remote_storage.py of the component MQTT+S3 Communication Backend. This manipulation of the argument s3_key_str causes deserialization. Remote exploitation of the attack is possible. The project was informed of the problem early through an issue report but has not responded yet.